Question

Dry ice is an example of …………..
A. Ionic crystal
B. Supercooled liquid
C. Molecular crystal
D. Covalent crystal

Answer 1

Hint: It is having weak intermolecular binding and they have evaporation heats two to three times lesser than the metals. Dry ice is the solidified carbon dioxide because it is very colder than ordinary ice.

Complete answer:
> Dry ice is a solid carbon dioxide which is generally used in packaging of frozen items. It is an example of molecular crystal. Dry ice releases a large volume of carbon dioxide gas as it sublimes at\[ - 78^\circ C\]. Dry ice is a molecular crystal, in which the crystal lattice consists of molecules of carbon dioxide rather than of individual carbon or oxygen atoms. Carbon dioxide is a non – polar molecule.
Ionic crystal: There is a regular arrangement of positively and negatively charged ions throughout the solid where ions are held together by strong electrostatic forces. These solids are very hard and brittle and have very high melting points. They are soluble in polar solvents but insoluble in non – polar solvents. For example, $NaCl,{\text{ KN}}{{\text{O}}_3},$ etc.
> Supercooled liquid: These types of liquids are known as an amorphous solid. They have a tendency to flow.
> Covalent crystal: In this type of crystal, the atoms are bonded together by covalent bond formation throughout the crystal. It means there is a continuous network of covalent bonds forming a giant three-dimensional crystal structure. For example: diamond, graphite, etc.
From the above discussion we can say that dry ice is an example of molecular crystal.


Hence, the correct option is C.


Note: Dry ice is colorless, nonflammable, with a sour zesty odor and can lower the pH of a solution when dissolved in water forming carbonic acid. Dry ice can’t be stored in an airtight container because carbon dioxide gas needs room to expand and it could cause your cooler to explode if you don’t remove the plug.